It is generally known to provide emergency response vehicles such as fire fighting vehicles for responding to fires on equipment, such as moving equipment (e.g. aircraft or the like, etc.). The vehicles are typically equipped with pumps that are driven at a predetermined speed (e.g. 2300 rpm, etc.) by the drive train or system of the vehicle for delivering a fire fighting agent or suppressant to the aircraft. Conventional fire fighting vehicles that use a pump operated by the vehicle drive train tend to have limited mobility because the drive train output (power) is directed away from the wheels of the vehicle for operation of the pump. The limited mobility of conventional fire fighting vehicles tends to reduce their effectiveness in fighting certain fires because the vehicle is usually inhibited from “following” a moving target or repositioning about a stationary target to continuously deliver a fire suppression agent from various advantageous angles of attack.
Certain systems have been developed to permit limited movement of a fire fighting vehicle during operation of the pump (e.g. slow rolling or “creeping” movement of the vehicle in a “pump and roll” mode of operation). However, such systems tend to have certain disadvantages. For example, such known pump and roll systems typically use a component of the vehicle's drive system (such as a transmission) to redirect a portion of the drive train output from the pump to the wheels of the vehicle, however, when an operator desires to stop the vehicle during operation of the pump, the operator usually has to manually apply the brakes, resulting in an additional operation by the operator and a potential distraction from the operator's attention on fighting the fire.
Accordingly, it would be desirable to provide a system for movement of a fire fighting vehicle during operation of a fire suppression pump. It would also be desirable to provide a system to permit movement of the vehicle while the vehicle drive train is used to operate auxiliary equipment (such as a pump for a fire suppression agent). It would also be desirable to provide a system for pump and roll operation of the vehicle that does not significantly reduce the speed of the pump. It would be further desirable to provide a system that permits operation of the vehicle in a pump and roll mode of operation through use of the braking system of the vehicle. It would be further desirable to provide a system that permits the vehicle to move slowly during a pump and roll mode when the vehicle's accelerator is actuated (e.g. “depressed”) and that stops movement of the vehicle when the accelerator is released without the operator having to separately apply the brakes of the vehicle.
Accordingly, it would be desirable to provide a pump and roll system for a vehicle having any one or more of these or other desirable features.